西洪大桥钢主塔竖向转体施工技术

Vertical Swivel Construction Technology of Steel Main Tower of Xihong Bridge

西洪大桥是广元快速路跨越余姚江的节点工程,为独塔双层钢桁梁斜拉桥,跨径布置为82 m+138 m+116 m,总长336 m。其主塔外形为弧形门式,采用混合塔结构,主塔下部为实体混凝土结构,上塔柱为钢结构。钢塔柱高82.044 m,采用竖向转体施工,转体质量为1 150 t,是整座大桥施工的重难点。主要介绍了弧形门式钢主塔竖向转体施工与设计,重点描述了竖向转体结构体系中三角形构架系统、转铰系统、牵引及背索系统、塔上锚固构造和塔梁临时固结的设计以及钢主塔竖向转体施工质量控制要点和措施。西洪大桥钢主塔竖向转体施工的成功实施为其他类似工程积累了新经验。

Xihong bridge is a node project of Guangyuan Expressway Crossing Yuyao river. It is a single tower double-layer steel truss cable-stayed bridge with a span of 82 m+138 m+116 m and a total length of 336 m. The shape of the main tower is arc portal type, which adopts mixed tower structure. The lower part of the main tower is solid concrete structure, and the upper tower column is steel structure. The steel tower column is 82.044 m high. It is constructed by vertical swivel with a swivel mass of 1 150 t, and is the key and difficult points of the whole construction.This paper mainly introduces the vertical swivel construction and design of arc portal steel main tower, focusing on the design of triangular frame system, swivel hinge system, traction and back cable system, anchorage structure on the tower and temporary consolidation system of tower beam in the vertical swivel structure system, as well as the key points and measures of vertical swivel construction quality control of steel main tower. The successful vertical swivel construction of the main steel tower of Xihong bridge has accumulated new experience for other similar projects.